Burns pt 1 Flashcards
What are the 2 major causes of death in burn patients?
Multiple organ failure and infection
How are burn injuries classified?
Burn injuries, regardless of their etiology, are classified according to the depth and extent of skin and tissue destruction, as well as the Total Burn Surface Area (TBSA) involved.
What are First Degree Burns?
First-degree (superficial) burns are limited to the epidermis, the outermost layer of skin. Think sunburn.
What are Second Degree Burns?
Second-degree burns, also known as deep and superficial partial-thickness burns, extend to the dermis.
What are Third Degree Burns?
Third-degree burns, or full-thickness burns, extend to the subcutaneous tissue lying below the dermis. The entire skin thickness is destroyed with third-degree burns.
What are Fourth Degree Burns?
A fourth-degree burn classification is used by some to describe structures burned below the dermis, such as muscle, fascia, and bone. (more seen with electrical injuries)
What does the Rule of Nines calculate?
The severity based on the amount of surface area covered in second and third-degree burns.
What is the percentage associated with the arms, head, legs, and torso?
Arms - 9%
Head - 10%
Legs - 18%
Torso - 36%
What is a Major Burn?
-A second-degree burn involving more than 10% of the TBSA in adults or 20% at extremes of age
-A third-degree burn involving more than 10% of the TBSA in adults
-Any electrical burn
-A burn complicated by smoke inhalation.
What are the 4 types of burn injuries?
-Thermal
-Electrical
-Chemical
-Inhalation
Describe Thermal Burns
(43% flame, 34% scald, 9% contact, 7% other)
-Commonly occur in/around the home
-Scald injuries predominantly children
Describe electrical burns
-Extent of burn depends on amount of thermal energy conducted through the skin
-10-46% cardiac arrhythmias and myocardial damage
-Severe damage to bones, blood vessels, muscle and nerves
-Myoglobinemia increased risk of renal failure
Describe Chemical burns
-Commonly occur in a laboratory/industrial setting
-Skin disruption continues until irritant is removed/neutralized
-Initial Tx: application of copious amount of water or NS irrigation
Describe Inhalation burns
-Often accompany a thermal burn, airway damage can vary
-Classification based on anatomic location:
Upper-airway, lower-airway, and metabolic asphyxiation. All 3 types may coexist in the burn patient.
What are the warning signs of respiratory injury?
-hoarseness
-sore throat
-dysphagia
-hemoptysis
-tachypnea
-the use of accessory muscles
-wheezing
-carbonaceous sputum
-elevated carbon monoxide levels
-Observance of soot around nose/mouth
What is the biphasic organ response to burn injury?
The treatment of the burn patient will evolve as they progress through the early resuscitative phase to the later hypermetabolic state.
-Early changes and later changes differ based on organ system
What are the early changes associated with organ response to burn injury?
-CV: Shock
-U: Oliguria
-GI: Ileus
-MSK: Hypoperfusion
-Pulm: Hypoventilation
-Endo: Catabolism
-Immuno: Inflammation (SIRS)
-CNS: Agitation
What are the Late changes associated with organ response to burn injury?
-CV: Hyperdynamic
-U: Diuresis
-GI: Hypermotility
-MSK: Hyperperfusion
-Pulm: Hyperventilation
-Endo: Anabolism
-Immuno: Suppression
-CNS: Obtundation
What are the 3 phases of management of the burn patient?
-Resuscitative Phase
-Burn Management: Debridement & Grafting
-Reconstructive Phase
What is the goal of burn therapy?
The goal of burn therapy is to rapidly restore skin integrity.
What are the pulmonary changes associated with burns?
-Decreased FRC and Chest wall compliance if chest wall burned
-Fluid shifts, interstitial edema, release of inflammatory mediators = pulmonary edema
-Significant a-A Gradient increases (Minute Ventilation increases to 40 L/min from normal 6 L/min)
-CXR normal in early phase progressing to pulmonary edema
Why is the burned patient at risk for Pulmonary Edema?
-Impaired vascular/capillary permeability combined with fluid resuscitation
-Mechanical ventilation often required especially with concomitant inhalation injury
What is important to know regarding ALI & ARDS and the burned patient?
-Acute onset of impaired oxygen exchange; partial pressure of arterial oxygen/fraction of inspired oxygen (Pa o 2 /Fi o 2) ratio of less than 300.
-Increased risk M&M due to respiratory failure, hypoxia, multiorgan failure, and pneumonia
What are ventilation strategies to use in the burned patient?
-Low-volume lung protective ventilation reduces overinflation and barotrauma
-Use ideal body weight
-PEEP
-Modest permissive hypercapnia
-Nonconventional and high-frequency oscillatory modes of ventilation
What is the gold standard for airway eval in the burned patient?
Fiberoptic bronchoscope is the gold standard!
What is the treatment of upper airway injury?
Early endotracheal intubation secondary to glottic/facial edema worsening with resuscitation.
Which patients are at risk for airway damage?
Involving a fire that occurred in a closed space or the development of unconsciousness or stupor that prevented the patient from protecting their airway
How does injury differ above the oropharynx vs below the vocal cords?
Above the oropharynx: thermal injury produces inflammation that can occlude airway.
Below VC: damage is due to soot/chemicals (heat dissipates by this point).
Why do you avoid the use of Succinylcholine > 24 hours after burn injury?
-Ach receptor up-regulation occurs after burn injury
-Succ releases K+ = possible cardiac arrest
How does Carbon Monoxide cause its effects?
Binds to Hgb with 200 times greater affinity than O2.
-50-60% fire victims die from CO poisoning
What are the S/Sx of Carbon Monoxide poisoning?
-Metabolic acidosis
-Oxy-Hgb dissociation curve LEFT
-Dec O2 content on ABG
-Falsely elevated SpO2 reading (pulse ox doesn’t detect CO)
How do you diagnose CO poisoning?
COHgb levels using a laboratory co-oximeter
How do you treat CO poisoning?
-100% O2 until COHgb level < 5% or for 6 hours
-Hyperbaric O2 therapy debatable
How does Hydrogen Cyanide poisoning occur?
HCN poisoning is produced by the combustion of plastics, foam, paints, wool, and silk.
-Binds terminal cytochrome on the electron transport chain blocking the intracellular use of O2
What are the S/Sx of Hydrogen Cyanide poisoning?
-Hypoxia, lactic acidosis, elevated mixed venous saturation
-loss of consciousness, dilated pupils, seizures, hypotension, and tachypnea followed by apnea
What is the half-life of Hydrogen Cyanide?
1 hour (!)
What is the treatment for Hydrogen cyanide poisoning?
-Hydroxocobalamin (Vit B12a)
-Binds cyanide forming cyanocobalamin with direct renal excretion.
